Water Spinach
Ipomoea aquatica
Water spinach, or kalmi shak, is a fast-growing leafy green with hollow stems that thrives in wet soil or shallow water. It is cut repeatedly through the warm months and is very easy to grow in a tub.
Photo: Eric Guinther · CC BY-SA 3.0, via Wikimedia Commons
Essential Care Requirements
Light
Full sun, Partial sun
Watering
High
Keep the soil constantly wet; it can be grown in a container with standing water.
Soil
Rich, moist, clay-loam soil; pH 5.5–7.0.
Temperature and humidity
18–40 °C · High humidity
Feeding
Feed every two weeks with a nitrogen-rich liquid feed for tender shoots.
Pruning and propagation
Propagate by stem cuttings, seed
Cut shoots 15–20 cm long; side shoots regrow quickly.
Safe to eat when cooked. Grow it in clean water only, as it absorbs pollutants.
Top Cultivation Tips
Shop-bought stems root in water within days.
Grow in a tub without drainage holes.
Harvest often to keep shoots tender.
It is a restricted weed in some countries; keep it contained.
Common problems
Aphids
Small, soft-bodied insects that cluster on new shoots and buds, sucking sap and leaving sticky honeydew behind.
How to treat it →PestCaterpillars
The larvae of moths and butterflies, which chew holes in leaves, flowers and fruit and can strip a plant in days.
How to treat it →DiseaseWhite rust
A disease that forms white, chalky blisters on the undersides of leaves of mustard greens, amaranth, radish and other leafy crops.
How to treat it →
